BUG: adds citation_journal_title meta tag
BUG: adds citation_journal_title meta tag

It looks like google scholar may not be correctly indexing
papers by '<meta name=citation_conference_title>'. This adds
'<meta name=citation_journal_title>' with the same content.
Closes #299.

sbenthall/scipy_proceedings,michaelpacer/scipy_proceedings,sbenthall/scipy_proceedings,sbenthall/scipy_proceedings,michaelpacer/scipy_proceedings,michaelpacer/scipy_proceedings